Instruments are known for applying a dental composite material onto a tooth. A disadvantage of composite materials, however, is their tendency to adhere more or less to the instrument that is used to apply or shape them. As a result, and by way of example, the composite material has a tendency to be drawn off from the edges of the cavity, to be distributed inhomogeneously on the tooth surface, and to form air bubbles during the distribution.
To this end, instruments have been developed that address the challenges observed in the application of composite materials. For example, known instruments may include coatings such as TiN, or Teflon™, for example, on the working tip of the instrument to minimize the likelihood of the composite material adhering to the tip. Other instruments may include a vibrating tip. In instruments of this type, however, the tip may vibrate at a fixed frequency and/or amplitude, in which case the material adheres to the tip when the viscosity of the material reaches a predetermined level, characteristic of the particular material. For example, an instrument may apply a composite material with a predetermined, fixed output frequency of vibration. Initially, the viscosity of the material is reduced to an acceptable level by virtue of engagement of the instrument with the material. After a predetermined length of time of engagement, however, the viscosity of the material may reach a level at which the material adheres to the tip of the instrument, which is undesirable. The user may then be forced to clean or replace the instrument altogether. Similarly, for a predetermined output frequency of vibration, there may be a difference in the viscosity level of the composite material according to the depth of insertion of the tip of the instrument into the material, which may also result in adhesion of portions of the material having a particular level of viscosity.
It is therefore desirable to provide a dental instrument that addresses these and other problems associated with conventional instruments used to apply a dental composite material onto a tooth.